Zenith high-grade hits at historic mine boost Qld gold push
Zenith Minerals has confirmed high-grade gold at surface at its wholly owned Auburn gold project in Queensland, with fresh grab rock-chip samples from last December returning up to a whopping 6.76 and 7.96 grams per tonne (g/t) gold.
The samples were taken from the historic Blast mine workings, reinforcing strong mineralisation right at outcrop.
The results build on Zenith’s earlier reconnaissance work in 2022, which delivered a peak rock-chip hit of 23.3g/t gold at the nearby New Camp historic workings, northwest along strike from Blast.
That sample was one of nine that ran better than 1g/t gold out of a total of 49 samples collected.
The latest results also back up extensive multiple coherent soil gold anomalies that were picked up in a 200m-by-50m grid-based soil geochemical program run by the company in 2022. That program stretched over a strike distance of up to 600m.
The multiple re-confirmed soil anomalies appear to link key historic mining and prospecting sites, including Blast, New Camp and Big Wonder, along a north-west structural corridor, with a peak soil hit of 1.1g/t gold.
Although 1.1 grams per tonne gold might not leap off the page at first glance, it’s worth remembering this figure comes from a soil sample, not a rock chip - making it a particularly strong geochemical result.
By way of example, soil sampling programs often test for gold at parts per billion – a tiny fraction of a gram- and many a valuable modern discovery has arisen from a handful of gold results at levels between 1 and 5 parts per billion (ppb).
Such low levels of detection were either impossible or too expensive to achieve with historical techniques, leaving some of the best discoveries untouched
In short, that 1.1g/t soil hit equates to an 1100ppb surface gold geochemical response – the sort of number that makes a geochemist’s eyes really pop from their sockets.
The Auburn results highlight a consistent gold footprint across multiple prospects within the project area. Recent high-grade grab sampling, together with earlier Zenith rock chip and soil results, reinforces the prospectivity of the system.
Auburn sits along the eastern margin of the Auburn Arc in the New England Orogen. It is an underexplored gold district with historic production from the 1880’s to about 1915, when WW1 interrupted so many prospecting and mining ventures.
The project hosts numerous shallow historic workings, many among outcropping rocks, with only a minor incidence of burial under younger cover. Despite straightforward access, modern systematic exploration has been sparse.
Previous operators, including Newmont, Kirk River Mining and Compass Resources, carried out only limited shallow trenching, selective sampling and very shallow drilling from the 1970’s through to the 1990’s. Most holes stopped at less than 10 metres depth - leaving deeper zones and strike continuity largely untested.
Gold at Auburn is hosted in granitic intrusives with strong alteration and limited quartz veining in higher-grade zones - features consistent with an intrusion-related gold system (IRGS).
Such systems often deliver broad, laterally extensive and vertically continuous mineralisation, pointing to solid upside potential for Zenith.
To chase that possibility, Zenith is gearing up for an expanded exploration program, comprising of infill soil sampling across a more detailed 100m by 50m grid and extending the tests along identified corridors.
Zenith also plans to launch new soil geochemical programs over priority prospects such as Truszes, Dreams of Avarice and Feldspar, combined with more rock-chip sampling and mapping of historic workings.
The new field work aims to confirm strike continuity between key sites and refine targets ahead of a scout reverse-circulation (RC) drilling blitz, which the company plans to kick off before mid-year, subject to permits and final planning.
The new proposals are almost certain to sharpen focus on Zenith’s growing Queensland gold footprint.
Auburn complements the company’s nearby flagship Red Mountain gold project, which is also in the Auburn Sub-province, offering a proven IRGS and/or breccia-pipe setting.
Such settings are similar to other previously mined giant gold systems in Queensland, such as the 3.5-million-ounce Mt Leyshon, the 5.1-million-ounce Kidston and 2-million-ounce Mt Rawdon gold projects.
Red Mountain continues to deliver scale with broad intercepts, such as a recent 325 metre intercept assaying 0.56g/t gold, including 139.7m at 1.05 g/t gold, accompanied by visible gold at depth.
Metallurgical tests on Red Mountain material indicate low-arsenic samples with excellent free-milling characteristics, average recoveries of 83.3 per cent and up to 95.8 per cent, with good gravity gold recovery.
With supportive current gold prices and Zenith’s disciplined push into underexplored but prospective ground, Auburn adds another high-potential layer to the company’s portfolio as drilling draws close.
Is your ASX-listed company doing something interesting? Contact: matt.birney@wanews.com.au
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